^^ it takes 4 to 6 weeks to get into your body...funny i have been on this for 4 years now for my SuddenTramic stress syndrome...it has done very well, and i keep up the blood works...lately though i feel i have been sleeping alot, Dr.s on Wednesday so for me, a good question to ask...ooh ya..plus the price of it has been going down quiet a bit too....100, to 80 now 60 dollars for 20mg for 100's...